I actually started reading eBooks over a decade ago on a Palm PDA. My eBook viewing device these days is an Android tablet,. using the open source FBReader for Android proqram to view the books. FBReader gets the nod because it reads ePub, Mobi, and FB2 (a Russian etext format) "native", and can display PDF, DjVu and other formats via plugins. I prefer ePub, but don't mostly have to care what form a book is in. (FBReader does not handle books with DRM, but I don't get DRMed titles and don't care.)
The tablet gets the nod over a dedicated reader because most dedicated eBook reader devices use eInk screens and are monochrome in consequence. Too much of what I read needs color, like volumes on art and art history. I've never had a problem reading on an LCD screen, so ease of reading on eInk isn't a factor.
But eBooks are an alternate format here. I have volumes on things like art, architecture, photography and design in paper, because they simply need a larger viewing area than a practice eBook viewing device can have. "Coffee table" books just don't work on portable devices. And for similar reasons, I don't normally try to read PDFs on the tablet. It's possible to create PDFs that reflow to fit the device screen, but most aren't created that way, and sideways scrolling to view a too wide document is actively painful.
The advantage to an eBook viewing device is that I can carry a library around with me. My library is stored on an external microSD card and has thousands of volumes. I normally have several in progress at a time, and I can read where ever I happen to be, whenever I have a moment. The
amount I read has gone up in consequence. eBooks also allow searching of the content, and custom bookmarks and annotations.
The other advantage to eBooks is that you don't call the EMTs if my To Be Read stack topples over on me. Since that stack is in round thousands at the moment, that's a boon.